package www.lagou.utils;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class DruidUtils {

    //1.定义一个成员变量
    public static DataSource dataSource;

    static {
        try {
            //3.创建属性集对象
            Properties p = new Properties();

            //4. 加载配置文件 Druid 连接池不能够主动加在配置文件, 需要指定文件
            InputStream inputStream = DruidUtils.class.getClassLoader().getResourceAsStream("druid.properties");

            //5. 使用Properties对象的 Load方法 从字节流中读取配置信息
            p.load(inputStream);

            //6.通过工厂类获取连接池对象
            dataSource = DruidDataSourceFactory.createDataSource(p);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    //获取连接
    public static Connection getConnection() {
        try {
            return dataSource.getConnection();
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        }
    }

    //获取数据库连接池的方法
    public static DataSource getDataSource(){
        return dataSource;
    }
    //4.释放资源方法
    public static void close(Connection connection, Statement statement){
        if (statement != null && connection !=null) {
            try {
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

    }

    public static void close(Connection connection, Statement statement, ResultSet resultSet){
        if (statement != null && connection !=null && resultSet != null) {
            try {
                resultSet.close();
                statement.close();

            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

    }
}
